The present invention relates to an information management system for a drive apparatus including a rotary electrical machine and a rotation sensor detecting a rotation position of a rotor of the rotary electrical machine, and a method of manufacturing such a drive apparatus.
A drive apparatus including a rotary electrical machine (motor or generator) is provided with a rotation sensor for precisely detecting a rotation position of a rotor with respect to a stator, so as to perform accurate speed control of the rotary electrical machine. The reason for precisely detecting the rotation position of the rotor by the rotation sensor in this manner is that a current value and a current phase to be input to the rotary electrical machine are determined based on an output signal from the rotation sensor.
When assembling such a drive apparatus, it is quite rare to have absolutely no assembly error between the rotary electrical machine and the rotation sensor by one time of assembly. Due to this assembly error and the like, a phase difference may occur between the rotary electrical machine and the rotation sensor. Here, when paying attention to the phase of a certain region in a circumferential direction of the rotor of the rotary electrical machine, “a phase difference between the rotary electrical machine and the rotation sensor” means a phase difference between a rotation phase of this certain region and a rotation phase of a region of the rotation sensor corresponding to the certain region (the same applies below). Accordingly, for aligning the phases between these regions, it is necessary in general to adjust the phase difference therebetween at least once.
As a method of adjusting the phase difference between the rotary electrical machine and the rotation sensor, Japanese Patent Application Publication No. JP-A-2005-295639 below describes a method of generating a back electromotive force by rotating the rotation shaft of the rotary electrical machine after assembly, comparing a voltage waveform of the rotary electrical machine with a voltage waveform for detection of the rotation sensor, and manually rotating the rotation sensor in a circumferential direction with respect to the rotary electrical machine when the phase difference therebetween is out of a predetermined range. In this method, the above operation is repeated until the phase difference comes within the predetermined range. Further, Japanese Patent Application Publication No. JP-A-S61-10715 below describes a method of measuring an error of the rotation sensor and storing the error in a storage unit of a control device controlling the rotation sensor in advance, and obtaining an accurate position based on the stored error information and detection values detected by the rotation sensor.